Character printing apparatus

Abstract

Apparatus for printing characters on a printout surface comprise a shaft having a longitudinal axis, a plurality of curved segments mounted side by side on the shaft for individual angular movement about the axis, each of the segments having a series of character types on an outer curved surface and a distinct first surface feature, such as a projection or a recess, behind each of the character types in an inner curved surface. The segments are also movable toward and away from the printout surface perpendicularly to the mentioned axis. The apparatus further includes equipment for selectively positioning the character types adjacent the printout surface, including devices for individually moving the segments angularly relative to the mentioned axis and for selectively resetting the segments to a rest position. The apparatus further includes equipment for selectively moving the shaft and segments toward and away from the printout surface, including a print hammer structure having a second surface feature for engagement of the segments at the first surface features behind athe selectively positioned character types of the angularly moved segments, and equipment coupled to the hammer structure for actuating the angularly moved segments at the first surface features with the print hammer structure toward the printout surface for a printout of the characters on the selectively positioned character types.

I claim: 
     
       1. In apparatus for printing characters on a printout surface, the improvement comprising in combination: a shaft having a longitudinal axis;   a plurality of curved segments mounted side by side on said shaft for individual angular movement about said axis, each of said segments having a series of character types on an outer curved surface and a distinct first surface feature behind each of said character types in an inner curved surface;   means connected to said shaft for mounting said shaft for movement together with said segments toward and away from said printout surface perpendicularly to said axis;   means operatively associated with said segments for selectively positioning said character types adjacent said printout surface, said character type positioning means including means for individually moving said segments angularly relative to said axis and for selectively resetting said segments to a rest position; and   means operatively associated with said segments for selectively moving said shaft and segments toward and away from said printout surface, said segment moving means including a print hammer structure having a second surface feature constructed for simultaneously engaging said angularly moved segments at their first surface features behind the selectively positioned character types, and means coupled to said hammer structure for actuating said print hammer structure toward said angularly moved segments and said printout surface for a printout of said characters on said selectively positioned character types, said first and second surface features being mutually complementary;   said means for individually moving said segments including for each segment an individual actuating rod having a longitudinal axis, means coupled to said actuating rod for selectively moving the actuating rod along said longitudinal axis, means coupled to the particular segment and operatively associated with said actuating rod for translating movement of said actuating rod along said longitudinal axis into angular movement of the particular segment relative to said axis, and means for mounting said actuating rod for angular movement during movement of said segments toward and away from said printout surface; and   said translating means including a ratchet teeth structure for each of said segments, and said means for moving said actuating rod including means for moving said actuating rod into engagement with said ratchet teeth structure for angular movement of the particular segment.   
     
     
       2. Apparatus as claimed in claim 1, wherein: said first surface feature comprises a projection; and   said second surface feature comprises a recess congruent with at least part of said projection.   
     
     
       3. Apparatus as claimed in claim 1, wherein: said first surface feature comprises a convex projection; and   said second surface feature comprises a concave recess congruent with at least part of said projection.   
     
     
       4. Apparatus as claimed in claim 1, wherein: said first surface feature comprises a recess; and   said second surface feature comprises a shape congruent with at least part of said recess.   
     
     
       5. Apparatus as claimed in claim 1, wherein: said first surface feature comprises a concave recess; and said second surface feature comprises a convex shape congruent with at least part of said recess. 
     
     
       6. Apparatus as claimed in claim 1, wherein: said means for individually moving said segments include actuator rods, means for mounting said actuator rods for angular movement relative to a longitudinal axis in response to movement of said segments toward and away from said printout surface, means for individually moving each of said actuator rods along a longitudinal axis, and means for translating longitudinal movement of each actuator rod into individual angular movement of a corresponding segment.   
     
     
       7. In apparatus for printing characters on a printout surface, the improvement comprising in combination: a shaft having a longitudinal axis;   a plurality of curved segments mounted side by side on said shaft for individual angular movement about said axis, each of said segments having a series of character types on an outer curved surface and a distinct first surface feature behind each of said character types in an inner curved surface;   means connected to said shaft for mounting said shaft for movement together with said segments toward and away from said printout surface perpendicularly to said axis;   means operatively associated with said segments for selectively positioning said character types adjacent said printout surface, said character type positioning means including means for individually moving said segments angularly relative to said axis and for selectively resetting said segments to a rest position;   means operatively associated with said segments for selectively moving said shaft and segments toward and away from said printout surface, said segment moving means including a print hammer structure having a second surface feature constructed for simultaneously engaging said angularly moved segments at their first surface features behind the selectively positioned. character types, and means coupled to said hammer structure for actuating said print hammer structure toward said angularly moved segments and said printout surface for a printout of said characters on said selectively positioned character types, said first and second surface features being mutually complementary; and   said resetting means including means for biasing said segments toward a rest position, releasable means for retaining said segments in angularly advanced positions against said bias, and means connected to said releasable retaining means and said means for selectively moving said segments toward and away from said printout surface for releasing said retaining means in response to movement of said segments relative to said printout surface for a release of said segments to said rest position.   
     
     
       8. Apparatus as claimed in claim 7, wherein: said resetting means include means for imposing a predetermined time delay on movement of said retaining means.   
     
     
       9. In apparatus for printing characters on a printout surface, the improvement comprising in combination: a shaft having a longitudinal axis;   a plurality of curved segments mounted side by side on said shaft for individual angular movement about said axis, each of said segments having a series of character types on an outer curved surface and a distinct first surface feature behind each of said character types in an inner curved surface;   means connected to said shaft for mounting said shaft for movement together with said segments toward and away from said printout surface perpendicularly to said axis;   means operatively associated with said segments for selectively positioning said character types adjacent said printout surface, said character type positioning means including means for individually moving said segments angularly relative to said axis and for selectively resetting said segments to a rest position;   means operatively associated with said segments for selectively moving said shaft and segments toward and away from said printout surface, said segment moving means including a print hammer structure having a second surface feature constructed for simultaneoulsy engaging said angularly moved segments at their first surface features behind the selectively positioned character types, and means coupled to said hammer structure for actuating said print hammer structure toward said angularly moved segments and said printout surface for a printout of said characters on said selectively positioned character types, said first and second surface features being mutually complementary; and   said resetting means including means for biasing said segments toward a rest position, releasable means for retaining said segments in angularly advanced positions against said bias, and selectively actuable electromechanical means for releasing said retaining means for a release of said segments to said rest position.   
     
     
       10. In apparatus for printing characters on a printout surface, the improvement comprising in combination: a shaft having a longitudinal axis;   a plurality of curved segments mounted side by side on said shaft for individual angular movement about said axis, each of said segments having a series of character types on an outer curved surface and a distinct notch behind each of said character types in an inner curved surface;   means connected to said shaft for mounting said shaft for movement together with said segments toward and away from said printout surface perpendicularly to said axis;   means operatively associated with said segments for selectively positioning said character types adjacent said printout surface, said character type positioning means include means for individually moving said segments angularly relative to said axis and for selectively resetting said segments to a rest position; and   means operatively associated with said segments for selectively moving said shaft and segments toward and away from said printout surface, said segment moving means including a print hammer structure constructed for simultaneous entry into the notches behind the selectively positioned character types of said angularly moved segments, and means coupled to said print hammer structure for actuating said print hammer structure toward said angularly moved segments and said printout surface for a printout of the characters on said selectively positioned charcter types;   said means for individually moving said segments including for each segment an individual actuating rod having a longitudinal axis, means coupled to said actuating rod for selectively moving the actuating rod along said longitudinal axis, means coupled to the particular segment and operatively associated with said actuating rod for translating movement of said actuating rod along said longitudinal axis into angular movement of the particular segment relative to said axis, and means for mounting said actuating rod for angular movement during movement of said segments toward and away from said printout surface; and   said translating means including a ratchet teeth structure for each of said segments, and said means for moving said actuating rod including means for moving said actuating rod into engagement with said ratchet teeth structure for angular movement of the particular segment.   
     
     
       11. Apparatus as claimed in claim 10, wherein: said print hammer has a convex cylindrical surface; and   each of said notches has a concave surface congruent with at least part of said cylindrical surface.   
     
     
       12. Apparatus as claimed in claim 11, wherein: said convex surface is circular cylindrical.   
     
     
       13. In apparatus for printing characters on a printout surface, the improvement comprising in combination: a shaft having a longitudinal axis;   a plurality of curved segments mounted side by side on said shaft for individual angular movement about said axis, each of said segments having a series of character types on an outer curved surface;   means connected to said shaft for mounting said shaft for movement together with said segments toward and away from said printout surface perpendicularly to said axis;   means connected to said segments for biasing said segments to rest position;   means operatively associated with said segments for selectively positioning said character types adjacent said printout surface, said character type positioning means including means for individually moving said segments angularly against said bias and relative to said axis;   first releasable means for retaining said segments in angularly advanced positions against said bias;   second releasable means, distinct from said first releasable means, for retaining said segments in angularly advanced positions against said bias, said second releasable means including means for engaging said angularly moved segments and for moving said shaft and engaged segments toward said printout surface for a printout of said positioned character types;   means operatively associated with said first releasable means for releasing said first releasable means after engagement of said segments by said engaging means; and   means for releasing said second releasable means and for returning said segments in a direction away from said printout surface after movement of said segments toward said printout surface.   
     
     
       14. Apparatus as claimed in claim 13, wherein: said segment engaging means include a print hammer structure for pressing said angularly moved segments against said printout surface.   
     
     
       15. Apparatus as claimed in claim 14, wherein: each of said segments has a distinct notch behind each of said character types in an inner curved surface; and   said print hammer structure is constructed for simultaneous entry into the notches behind the selectively positioned character types.   
     
     
       16. Apparatus as claimed in claim 14, wherein: each of said segments has a distinct protrusion behind each of said character types in an inner curved surface; and   said print hammer structure is constructed for simultaneous engagement of the protrusions behind the selectively positioned character types.   
     
     
       17. Apparatus as claimed in claim 13, wherein: said means for releasing said first releasable means include means for sensing movement of said segments toward said printout surface and means connected to said sensing means for releasing said first releasable means in response to said movement toward said printout surface.   
     
     
       18. Apparatus as claimed in claim 17, including: timing delay means connected to said first releasable means for imposing a predetermined time delay on a movement of said first releasable means.   
     
     
       19. Apparatus as claimed in claim 13, including: electromechnaical means for selectively operating said first releasable means.   
     
     
       20. Apparatus as claimed in claim 13, wherein: said means for individually moving said segments include for each segment an individual actuating rod having a longitudinal axis, means coupled to said actuating rod for selectively moving the actuating rod along said longitudinal axis, means coupled to the particular segment and operatively associated with said actuating rod for translating movement of said acutating rod along said longitudinal axis into angular movement of the particular segment relative to said axis, and means for mounting said actuating rod for angular movement during movement of said segments toward and away from said printout surface.   
     
     
       21. Apparatus as claimed in claim 20, wherein: said translating means include a ratchet teeth structure for each of said segments, and said means for moving said actuating rod include means for moving said actuating rod into engagement with said ratchet teeth structure for angular movement of the particular segment.   
     
     
       22. Apparatus as claimed in claim 13, wherein: said means for individually moving said segments include actuator rods, means for mounting said actuator rods for angular movement relative to a longitudinal axis in response to movement of said segments toward and away from said printout surface, means for individually moving each of said actuator rods along a longitudinal axis, and means for translating longitudinal movement of each actuator rod into individual angular movement of a corresponding segment.